6L80e shift flare, please help Russ K

[Bossy70]

I have a 2010 Tahoe w/ Magnuson 1900 on 5.3L. I used Russ K's transmission tune (from: http://www.hptuners.com/forum/showth...silverado-tune) for my 6L80e.

I am getting part throttle shift flare SOMETIMES (especially when cold) on 3-4 and 4-5. I have not tuned WOT, not that far yet. I have ran the reset/relearn on the scanner. It seems to do awesome sometimes and bad others. I hope this flare does not cause damage.

Do I need adjusted shift times? adjusted Pressures? both?

Russ left "max pressure" parameter stock, so I did also... before this I ran Magnuson/Diablosport hybrid tune that increased that to 125 and changed some of the other tables. The tune Magnuson alone gave me some shift flare but they had fooled with the TM torque numbers. After I loaded the Diablosport transmission tweak it seemed consistent. I thought about taking the 3-4 and 5-6 shifts from that tune but I would like to do this the correct way.

Any help is appreciated.

Thanks,

Current tune and a short part throttle datalog is attached.

Homebuilt_Tahoe_AS9.hpt
trans2-short.hpl

[Russ K]

What's with the -32 sec on the min downshift times? Why did you change the pressure pattern select fields? Some of your shift tables are not 60psi over stock, recheck those. Also I never found a need to change the oncoming & off going pressure preset tables. Return the oncoming volume preset 3-4 & 3-4 sp back to stock. Return the min adapt volume fields to stock.

I would return the shift torque factor fields to stock, then halve the cold modifier table to reduce the shift torque reduction by 50%. Then return the shift torque factor adder fields to stock, and return the adder modifier table to stock.

Russ Kemp

[Bossy70]

Thanks for your feedback!

I only put -32 on the min downshift times because that is what I saw on your tune I downloaded, but I now see a 2011 Sierra stock has those set at -32 for some reason. Overall I think I see what I did. I tried to copy over too much from that 2011 tune to mine. I incorrectly assumed 2010 and 2011 had all the same values, but GM apparently changed a lot of values between those two years.

Would you leave ALL torque and torque management values stock? Magnuson had torque higher than stock tune in several locations under Engine TM tab (Max Torque Gear charts, Trans I/O/axle/shaft, brake torque limit and TCS max torque) and one under Trans TM.

I made the modifications and here I am now. I will drive this around. Let me know if there are any comments about the attached.

Thank,

Homebuilt_Tahoe_AS11.hpt